Ameliorative Effect of Chelating Agents on Photosynthetic Attributes of Cd Stressed Sunflower
Excessive input of heavy metals in water reservoir and cultivated land primarily affects the growth and yield of crops. The aim of this work was to study the mechanism of Cd toxicity and damage to photosynthetic pigments and their efficiency and the potential of natural (OA) and synthetic chelators (EDTA) in assisting the phytoextractor sunflower plant. The pot experiment was laid out in a complete randomized way for Cd, chelators and hybrids at seedling, vegetative and reproductive stages with three replications. Cd affects the gas exchange parameters directly or indirectly by affecting the light and dark reactions, while indirect effect includes inhibition of chlorophyll and carotenoids biosynthesis and degradation and alteration in Chl a/b ratio. Among two chelators, natural chelator OA found to be very supportive in ameliorating the Cd tocixity by phytoextractor in assistance to sunflower hybrid Hysun-33.